Machine for cutting leaf tobacco and the like



March 22, '1949. P. Q. R. SCHREIBER MACHINE FOR CUTTING LEAF TOBACCO ANDTHE LIKE Filed Aug. 28, 1944 6 Sheets-Sheet 1 Imgentor A Ito! ne\ 5March-22, 1949. P. Q. R. SCHREIBER ,464, 9

MACHINE FOR CUTTING LEAF TOBACCO AND THE LIKE 6 Sheets-Sheet 2Filed'Aug. 28, 1944 20-19. g5cbre/zer;

Inventor Attorneys P. Q. R. SCHREIBER 2,464,896

March 22, 1949.

MACHINE FOR CUTTING LEAF TOBACCO AND THE LIKE 6 Sheets-Sheet 3 FiledAug. 28, 1944 Inventor A ltorney S March 1949- P. Q. R. SCHREIBERMACHINE FOR CUTTING LEAFTOBACCO AND THE LIKE 6 Sheets-Sheet 4 Filed Aug.28, 1944 I t PQJR Sabre/ 222 5 y w m A 'MACHINE FOR CUTTING LEAF TOBACCOAND THE LIKE Filed Aug. 28, 1944 March 22.' 1949- P. Q. R. SCHREIBER 6Sheets-Sheet 5 0 I. n e 0 n I g S cm @Mik r 6 vm e W 5 e a H y V 1 MAttorneys March 22, 1949. P. Q. R. SCHREIBER 2,464,896

MACHINE FOR CUTTING LEAF TOBACCO AND THE LIKE Filed Aug. 28, 1944 6Sheets-Sheet 6 FIGQ,

2/ [n Uenlor 12 643. Sabre 6e11,

J A llurneys Patented Mar. 22, 1949 UNITED STATES PATENT. OFFICE MACHINEFOR CUTTING LEAF TOBACCO AND THE LIKE Patrick Quintin Robert Schreiber,London, England Application August 28, 1944, Serial No. 551,573 In GreatBritain September 18, 1943 Claims. 1

before having to be removed for grinding. Such disadvantages areeliminated in the second type in which a small number, say five, ofknives are caused to rotate continuously and uniformly about an axis. Atone point in their path the knives pass grinding mechanism so that theyare kept sharp while the tobacco is being cut and the machine can be runfor substantial periods without stopping. However, certain disadvantagesare peculiar also to this type of machine.- For example, the arrangementof the grinding mechanism is such that the grinding wheel tends to glazeand has to be dressed continuously and automatically by a, diamond.Further, although an extraction fan is used to draw off grinding dust,

it is not possible to prevent a certain amount of dust finding its wayinto the cut tobacco.

One object of the present invention is, therefore, to eliminate theaforesaid disadvantages in regard to the grinding of the knives in arotary type of machine. mounting the knife assembly to be movedtoand-fro between a position on one side of the drum in which thetobacco is cut and a position on the other side of the drum in which itis acted on by grinding mechanism. Thus, the cutting of the tobacco leafis stopped when the grinding takes place but it does not have to bestopped at anything like such frequent intervals as the reciprocatingknife type of machine, particularly as a further object of the inventionis so to contrive the drum that a large number of knives are mountedthereon, all such knives, of course, being ground in a single grindingoperation. It may, at first sight be thought that it would be as easy tocause the grinding mechanism to approach the knife drum as to cause theknife drum to approach the grinding wheel or the like but this is notso. One reason is that it is desirable to grind the knives to apredetermined diameter and to do this it is necessary first to causethem to project slightly beyond the said diameter, which necessitateswithdrawing the drum from the mouthpiece through which the tobacco isfed.

It has already been mentioned that a particular object of the inventionis to construct the This object is achieved by "drum with a large numberof knives. It is defatigue the operator in'moving them about.

sirable for not more than one knife to be in engagement with the tobaccoat any one time and, therefore, in an example where the maximum heightof the tobacco being cut is three inches, the knives are slightly morethan three inches apart. A further advantage of using a large number ofknives is that a low cutting speed .can be obtained for a substantialoutput of tobacco.

In tobacco leaf cutting machines the tobacco is fed to the cuttingappliance through a mouthpiece defined by upper and lower jaws and it isadvantageous to mount one of the jaws so that it can yield. Hithertosuch a jaw has been loaded by weights or springs. Springs have thedisadvantage that they exert a changing pressure as their strainchanges, while weights are tiresome to ad ust and In neither case cantheactual pressure applied to the tobacco be ascertained instantly. Whenthe operator stops the machine for meals it is usual to relieve thepressure on the tobacco and in the said disadvantages.

case of weights or springs this involves a certain amount of manuallabour. Another object of the present invention, therefore, to 10d thejaw by hydraulic mechanism which overcomes the afore- Such a mechanismcan be provided with a pressure gauge that gives an instantaneousindication of the pressure on the tobacco and can be accurately adjustedwith great ease.

Further objects of the invention will appear from the ensuing portionsof this specification.

In order that the invention may be clearly understood and readilycarried into effect, a machine in accordance therewith will now be described by way of example, with reference to the accompanying drawings,in which Figure 1 is an elevation of one side of the machine,

Figure 2 is an elevation of the other side of the machine.

Figure 3 is a vertical section through the machine,

Figure 3A is a sectional elevation of a detail,

Figure 4 is a diagrammatic plan of certain portions of the machine,

Figure 5 is a sectional side elevation of certain details shown on amuch larger scale than in the preceding figures,

Figure 6 is a sectional plan of an assembly used in the machine,

Figure '7 is a sectional end elevation of the assembly appearing inFigure 6,

tobacco leaf is compressed as it is fed forwards.

and, immediately before reaching the knife drum, passes through amouthpiecedefinedby an upper jaw 4, mounted for up and down movement,and a lower jaw 5 which is fixed and =which 'serves as a cutting bedwith which knives 6, carried-by the knife drum, co-operate to severslices .of tobacco from the mass thereof as the drum rotates inclockwise direction as viewed in Figure 3.

It is an essential of good cutting of the tobacco -that it-shouldbe cutas close as possible to the mouthpiece where the tobacco isundercompres- 'sion; otherwise, the compressed tobacco expands and'anuneven width of cut results. Thus, it is desirable for the upper jaw 4to follow the periphery of the knife drumas it rises and falls.Furthermore, the lower face of the upper jaw should at alltimes besubstantially parallel to, or at a substantially constant angle withrespect to, the upper surface of the lower. jaw. Therefore, the upperjaw forms part of a parallelogram linkage being mountedat ea'chendona.pair

of links 1 and 8. The remote ends of the links I are pivotedrespectively on journals 9 (Figures 3 and 4) fixed to the machine framerespectively at each end of,'and in a vertical plane containing the axisof, the knife drum-l (when the latter is in its cutting-position). Theremote ends of the lower-linksB are also pivoted to the machine frame,being mounted on journals I (Figure 3) in the aforesaid plane butbeneath the axis of the knife drum. The ends of the upper jaw 4 areformed-with cheeks ll carrying journals [2 and I3 for the near ends ofthe links and -8.

The upper feed band-2 is carried-by a driving roll i4, fixed to adriving spindle I5, and a front roll 16 divided into three sections l6a,lGb, and IE0 (see Figure 4) freely mounted on a spindle IT. The spacingof the spindles l5 and I! is maintained constant by-a stretcher framecomprising side members l8 journalled on the saidspindles and rigidlyconnectedby cross members 19- and 20 to which are rigidly-fixed twolongitudinal members 22 which project between the sections 16a, 46b andI60 of the front roll it and which support the spindle I'l.

It will be appreciated that,-owing to the fact that thedistancebetweenthespindles l5 and I1 --is fixed, the spindle 15 must befree to move to-,

and-fro as the upper jaw 4 rises and falls on the links I and 8.Therefore, the spindle 15 is mounted in journal bearings 23 free toslide in guide slots '24 formed in the machine frame,

The spindle 15 carries a worm wheel 25 (shown diagrammatically inFigure 1) in'mesh with a worm 26 fixed to a shaft 21-whichat its otherend carries a second worm 28in mesh with a worm wheel 29 fixed to aspindle 30 (Figure 3) which has rigid therewith a feed roll 3!- for thelower feed band 3. The worm wheel 25 can roll slightly on its worm 26 asthe spindle 15 of the feedroll M for the upper feed band movesto-and-fro -as aforesaid. V

A pair of bevel gears 32and 33, showndiagram matically in Figure 1, aresplined to the shaft 21 and either can be caused, at will, to mesh witha bevel gear 34 that rotates continuously during the operation of themachine. Thus, the feed bands 2 and 3 can be caused to feed the tobaccoto the knife drum, or they can be reversedso as to clear the machine oftobacco, if lthis proves to be necessary. "The bevel gear 34 isconnected by gearing, including a worm wheel 35 and a worm 36, to ashaft 31 carrying a bevel gear 38 in mesh with a bevel gear 39 on acounter shaft'geared through gears 40 and 4| (Figure 2) to a shaft 42(Figure 1) carrying a pulley wheel 43 connected by a belt 44 to a pulleywheel 45 driven by an electric motor 46.

The feed bands 2 and 3 are of known constructionand'it is, therefore,unnecessary to describe them in great detail. They consist of brassslats hinged together and formed on their outer faces with grooves thatgrip the tobacco. On their inner faces theyare shaped to engage teethformed --in their respective driving rolls. Such teeth 41 longitudinalmembers 22. 5D 5! and 52 are carried by the machine frame and back theupper run of the lower feed band -3. The-various support rolls enablethe feed bands to react against'thepressure of the tobacco are shown onthe-driving roll M in Figure 3.

*A support roll 48 which backs the lower run of the feed band 2 iscarried by a spindle 49 carried by the side members l8 of the stretcherframe. The support roll 48 is, like the front roll l 15, divided intothree sections 48a, 48b and 48c (Figure 4) separated from each other bythe Similar support rolls as this is compressed between the convergingfeed bands.

The'lower feed band 3 extends backwards to a roll 53mounted ona spindle54 carried by journal bearings 55 located in slots 55 in the machineframe. The tension in the feed band 3 tends to cause the-journalbearings55 to slide forwards inthe 'slots 56 but their movement is limited byadjustable stops in the form of bolts 51 screwed into flanges 58 (on themachine frame) that define the ends of the slots 56.

It will be recalled that the upper jaw 4 is free to rise and fall.However, a downward thrust on the jaw is necessary to maintain therequired pressureon the tobacco. This pressure is furnishedhydraulically, oil being pumped from a reservoir-(not shown) by a smallhigh speed triple ramoil'pump, indicated diagrammatically at 59 inFigure 2. The oil is delivered through an inlet :65 to a cylinder 66pivoted at 61 to the base of the machine frame. The oil pressure tendsto lift a piston '68 carriedby a ram III that passes through -a gland llat-the topof the cylinder 66 and is .pivoted at-12 to a cross-head I3which extends .across the machine and has pivoted respectively at-itsends two-armed levers-14 which, in turn.

'arepivoted at their centres on trunnions '15 carried by the machineframe. At its forward end =each lever 14 is pivoted to an upwardlyextending link 18 pivoted-at Tl to the adjacent one of the side membersI8 of the stretcher frame. The

-cross-head I3 is urged downwards and the jaw'4 upwards against thehydraulic pressure by two vhelical tensionsprings'm, one on each side ofthe cylinder 66, connected between the crosshead and the base of themachine. The pressure beneath the piston 68in the cylinder 66 isdetermined' byan adjustable automatic springloaded relief valve (Figure3A) through which excessoil is returned to the reservoir. The reliefvalve-may take many-different forms of which lief valve.

that shown in Figure 3A is an example. This relief valve is connected bya pipe 65a to the inlet '65 and comprises a piston 65?) mounted to slidein a cylinder 65c and loaded by a spring 65d interposed between thepiston 65b and an abutment member 65c, screwed into the top of thecylinder 650. When the pressure in the inlet pipe 65 reaches apredetermined value, the piston 65a is lifted against the spring 65d soas to uncover a port 65] through which the oil can escape to thereservoir. The extent to which the abutment 65c is screwed into thecylinder 65c determines the stress in the spring and, therefore, the oilpressure at which the port 95 is uncovered. If the amount of tobaccobeing fed through the machine is constant, the piston 68 remainsstationary while all the oil delivered by the pump is by-passed throughthe relief valve back to the reservoir. A constant pressure is thenexerted on the tobacco, according to the setting of the re- If, on theother hand, the amount of tobacco becomes greater or less, the piston 68falls or rises While more or less oil is by-passed through the reliefvalve. If, at any time, it is desired to relieve the pressure on thetobacco, the relief valve is fully opened so that the oil drains fromthe cylinder 66 and the springs 78 lower the cross-head I3 while raisingthe jaw d.

The knife drum is a composite structure comprising, as shown in Figures6 and 7, a main drum member 89 mounted between end pieces BI and 82formed respectively with journals 83 and 84 by which the drum isrotatably mounted in the machine frame. Projecting inwardly from the endpieces 8| and 82 are spigots 85 and 86 which support an inner drummember 8'1. The latter is rotatably mounted on the spigots 85 and 89 butis normally caused, by means to be described presently, to rotate as aunit with the other portions of the drum. The outer surface of the maindrum member 88 is formed, as shown, for example, in Figure '7, with aseries of tangential fiat surfaces 91a. As clearly shown in Figures 3and 5, a knife support 88 is fixed to each of the surfaces 81a, eachsupport being a trough-shaped member extending substantially the wholewidth of the drum and being closed at each end by plates which carry aspindle 89 and an eccentric shaft 99.

Each of the knife supports 88 carries one of the knives 6, the frontwall GM of each support 88 being formed with a surface 92 (Figure 5)against Which the associated knife 6 is clamped at the required cuttingangle with respect to the drum. The clamping is effected by a member 93carried inside the support 88 by the spindle 89 upon which it ispivotally mounted through the medium of lugs 94 integral with the clampmember 93. The outer face of the latter is formed with a clamp surface95 corresponding to the surface 92. Just behind the surface 95 the clampmember 93 is formed with a longitudinal recess 98 which the mass oftobacco enters as it is severed by the knife 6 sweeping past themouthpiece defined by the jaws t and 5. The clamp member 93 ismaintained firmly in engagement with the knife 6 by means of theaforesaid eccentric shaft 9? which is formed with the eccentrics 9'!which, in the operative position of the shaft 90, are wedged againstsurfaces 98 on the inner face of the clamp member 93. To support theradial thrust on the eccentric shaft 96, half bearing blocks 99 areinterposed between the shaft 90 and the back wall Hill of the knifesupport 88, these bearing blocks arcuate aperture H2 in the end pieceBI.

slightmcvement of the inner drum member 81 99 being distributed alongthe shaft and locate between the eccentrics 91.

The mounting of each knife is such that, on entering the tobacco, itdoes not make contact therewith simultaneously at all points along itsedge but is set at a very slight angle so that the knife enters thetobacco progressively along its edge. The upward thrust on the knife isopposed by four two-armed levers IUI, distributed along the knife, eachof which project through an associated one of four apertures I02 in theback wall I of the knif support 88 and through a corresponding apertureI93 in the adjacent portion of the main drum member 89. The lever ispivoted at HM inside the aperture I93 upon lugs I projecting from theback wall I99.

It will be appreciated, therefore, that there are four levers IBIassociated with each knife 6, and the various levers are distributedround the inner drum 8'5 in four separate planes, each plane containingone of the levers for each knife 6. In each such plane the inner drum8'5 is formed with a peripheral ring I95 and each such ring is formedwith a series of slots l0! which respectively receive the inner endsIlla of the associated two-armed levers IUI. The four peripheral ringsI96 appear in section in Figure 6 and the engagement of one of the slotsIt? with the associated two-armed lever IGI appears clearly in Figure 5.

When the cutting edges of the knifes 6 become worn it is necessary toadjustthem in their support 89, and this is effected by turning theinner drum member 81 on the spigots 85 and 86. Such movement of the drummember 81 relatively to the main drum member 89 is brought about byturning a screw I99 threaded in a lug H0 carried by the end piece 8I(Figures 6 and 7). The inner end of the screw I99 then thrusts before itan arcuate projection III which is carried by the inner drum member 81and projects through an This about the axis of the main drum member 89results in the walls of the slots IB'I acting on the inner ends I08 ofthe two-armed levers iQI so as to turn the latter about their pivots I04and simultaneously thrust the knives 8 slightly further outwards fromtheir respective carriers 88. In the rotation of the knife drum as awhole, during the normal operation of the machine, the screw I99 bearscontinuously on the arcuate projection III, so rotating the inner drummember 8'! with the outer drum member Bil.

The journals 83 and 8d of the knife drum are mounted in journal bearingscarried by slots in the machine frame, the latter being disposed so asto enable the knife drum to be shifted a small distance towards, andaway from, its cutting position. The sectional plan of Figure 8 showsone of these journal bearings, which bears the reference numeral I I3,and it also shows the lower face II4 of the slot in which the journalbearing may be moved to shift the knife drum as aforesaid. Flanges II 5and H6 are formed on each journal bearing so as to maintain it axiallyin position with respect to the associated slot, the flanges engagingthe side faces of the slot. The journal 83 is connected, as shown inFigure 8, by'a dog clutch to a sprocket I I? through which the drum isrotated. The dog clutch comprises a member I I8 splined to the journal83 so as to rotate therewith while being free to move to-andfro in theaxial direction. The member H8 is formed with an annular groove IE9 in.which is mam so rlocated a crank I carried by a spindle I2I mounted in acover I22. Outside the cover I22 the spindle I2I carries a handle 123.Therefore, by turning the handle, the crank I20 may be caused to movethe member'II8 either towards or away from a position in which dogs onits inner face engage associated dogs on the outer face of the sprocketH1. The latter rotates continuously while the electric motor 46 is inoperation but the dog clutch just described enables the knife drum to bestarted or stopped at-will while other parts of the machine are inoperation. The

sprocket H1 is connected by a chain I24 toa sprocket I25 indicateddiagrammatically in Figure 2 and connected by a suitable train of gearsto the shaft 42 (Figure 1). This chain drivepermits of the smallto-and-fro motion of the journal bearings II3 as aforesaid to bringabout the movement of the knife drum towards and away from the tobaccomouthpiece. Thismovement is effected by mechanism shown-particularly inFigures 1, 2 and 8. Referring first to Figure'2, a ratchet wheel I26,which maybe turned either by mechanism to be described presently or-by ahandle I21, is mounted on a countershaftIZS.

carrying a pinion I29 in mesh with a gear wheel I30 mounted on a shaftI3I carrying a bevel wheel I32 which drives a bevel wheel 'I33 on ashaft I34 that extends across the machine and carries near each endbevel gears which respectively drive small vertical shafts I35 (Figure2) and I36 (Figure 1). The bevel gear that drives the shaft I36 appearsin Figure 1 and is designated I38. It meshes with a bevel gear 228 onthe shaft I36 which, atits upper end, carries a bevel gear 229 in meshwith a bevel gear 230 mounted on-a sleeve I39 having an internal screwthread which engages an external screw thread on a shaft I40. Similarlythe small vertical shaft I35 has, at its lower end, a bevel gear MI inmesh with the associated gear on the shaft I34 and, at its upper end, abevel gear I42 in mesh with'a bevel :gear I43 on a sleeve I44 containingan internal screw thread engaging a screw thread ona shaft I45. Thesleeves I39 (Figure 1) and I44 (Figu1'e 2) are mounted so that theycannot'undergo'any axial movement. Therefore, when the shaft =I34 iscaused to turn as a result of the turning of the ratchet wheel I26(Figure 2), the small vertical shafts I35 (Figure 2) and I36 (Figure '1)cause the shafts I45 and I to move longitudinally one way or the otheraccording to the direction in which the ratchet wheel is turned and suchmovement is communicated to the journal bearings carrying theknife drumI. Figure s' shows the shaft I connected to the journal bearing H3 andthe connection is a rigid connection soithat the shaft I45 will not turnabout its axis when the associated sleeve I44 turns. The connectionbetween the shaft I40 and the journal bearing at the other end of theknife drum-is precisely similar. The ratchet whee1 I26 is preferablyfurnished with an index which registe'rs with' a scale to enable theoperator to determine the precise position of the axis of the knifedrum.

To remove the tobacco from the recesses 96 in .the knife drum, theperiphery of the drum, after passing the fixed jaw 5, travels pastnozzles, at each end of the drum, through whichblasts of air blow thetobacco out of the recesses. The nozzles are supplied through a pipe I46from a blower I41 (Figure 3) driven by a belt 'I48 -from a pulley'filfixed to a pulley 62 driven by a belt 63'from'a pulley 64 driven by themotor 46.

necessary to re-sharpen them and this is effected by a grinding wheel(Figures 3, 8 and 9) mounted in the machine. This grinding wheel I50,during the grinding operation, is automatically moved to and fro acrossthe width of the knife drum. In initiating the grinding operation thefirst step is precisely to determine the plane'in which the grindingwheel is so to move to-andfro, and then through the medium of the handleI21 and the mechanism described above, to move the knife drum away fromthe tobacco mouthiece, defined by the jaws 3 and 4, to the position inwhich it is engaged by the grinding wheel I50, the knives 6 having firstbeen actuated by the aforesaid screw I09 to cause them to project farenough outwards to enable them to be ground down to a predetermineddiameter at which they are to start cutting after the grindingoperation. When the grinding operation has been initiated automaticmechanism becomes operative for moving the knife drum axis in smallsteps towards 'the grindingwheel as the sharpening of the knives '6progresses.

By turning a handle I5I carried by a shaft' I52 mounted on a bed I53which is traversed by a carriage I54 upon which the grinding wheel ismounted, the carriage I54 is caused to move along the bed I53. This isbecause the shaft I52 carries a gear wheel I55 in mesh with a gear wheel156 (Figure 3) on a countershaft I51 carrying a gear wheel I58 in meshwith a gear wheel I59 on a shaft I60 bearing gear wheel I6I in'm'eshwitha rack I62 on the carriage I54.

To initiate the grinding operation the handle 'i5I is turned in such adirection that the grinding wheel I50 is brought opposite a diamonddressing tool I63 (Figure 10) fixed to one side of the machine. Theposition of this diamond tool I63 determines the plane in which thegrinding wheel I56 is to act on the knives. The tool is mounted so thatit can be adjusted for wear. The grinding wheel I50 is caused manuallyto approach the diamond tool I63 by turning a handle I64 (Figures 3 and9)'mounted on a shaft carried by the carriage I54 and actingthroughmechanism, not shown and forming no part of the present invention, on aslide rest I65 mounted-to move at right angles to thedirection ofmovement of the carriage I54 and serving as a support by which thegrinding wheel I50 is attached to'the carriage I54. The slide rest I65also carries a motor I66 for driving the grinding wheel I50 through themedium of pulley wheels I61 and I66 and a belt I63. Assuming that themotor I66 has been started the grinding wheel I50 is causedlto :traversethe diamond tool I63 by manual opera- .tion of the handle-I5I so as todress the grinding wheel. During this operation a dog clutch, com-,-prising dog members I10 and HI, is disengaged,

the member I1I being held against the action of a spring I12 (by amanually operated cam I13 acting on a flange I 14) away from the dogmember I10. The latter rotates continuously during the operation of themachine while the do member I1I is splined to a shaft I15 by which thecarriage 'I54'is automatically driven when required.

The knife drum, while still being rotated by the chain I24, is moved tothe plane in which the grinding wheel I50 is to operate and when thishas been done the cam I13 is moved so as to allow the spring I12 tocause the dog member I1I to engage the member I10. Thus, the shaft I15is caused to rotate and this causes the carriage I64 When the knives 6have become bluntpitds 75 to move backwards and forwardsalong the vbedI53 through the medium of mechanism now to be described.

- This mechanism comprises two bevel gears I89 and i8l freely mounted onthe shaft I15. These bevel gears are formed respectively with dog teethI82 and I83 arranged to be alternately engagedby similar teeth I84 andI85 on sleeves I86 and I81 splined to the shaft I15. The sleeves I86 andI81 are formed respectively with annual rooves I98 and I99 that areengaged by pins I99 and I9I (Figure carried by levers I92 and I93pivoted at fixed points H34 and I95. The upper ends of the levers I92and I93 are pivotally connected to a horizontal bar I99 carrying twofixed abutments I I91 and I98 between which a lever I99 projects.

The lever I99 is pivotally mounted at a fixed point 299 and is formedwith a lateral projection 295 having at its extremity a V-shaped surface292. Let is be assumed that, as shown in Figure 9, the dog teeth I92 arein engagement with the dog teeth I84, while the dog teeth I85 areseparated from the dog teeth I93. This results in the bevel gear I9Idriving a bevel gear 293 with which it is in mesh. The bevel gear 293 isalso in mesh with the bevel gear I89 but, as the latter at this time isfree to rotate idly, the drive is transmitted through the bevel gearI8I. Thus, the bevel gear 293, which is mounted on the aforesaidcountershaft I69, turns the latter so as to move the carriage I54 andthe grinding wheel I59 to the right as viewed in Figure 9. As thecarriage I54 approaches the end of its stroke in this direction, a stop294 carried thereby engages the upper end of the lever I99 and moves itto the right so that the V-shaped surface 292 is caused to snap past asimilar V-shaped surface 295 on a plunger 296, which yields as a resultof this action against a compression spring 291 interposed between theplunger and an abutment 298 at the remote end of a cylinder whichcontains the plunger 296 and the spring 291. As the lever I99 snaps fromthe position shown in Figure 9 to the opposite position in which theV-shaped surface 29! lies below the V-shaped surface 295, it engages theabutment E98 and shifts the horizontal bar I96 to the right carryingwith it the upper ends of the levers I92 and I93 which, throughthe-medium of the pins I99 and I9I, shift the sleeves I86 and I81 todisengage the bevel gear I8I and engage the bevel gear I89. Thus, thebevel gear 293 is now driven by the shaft I15, not through the bevelgear i9l, but through the bevel gear I99, so that the carriage I 54 isdriven in the reverse direction back towards the position shown inFigure 9. On reaching the end of this reverse stroke, a stop 299 engagesthe lever I99 and causes it to snap back to the position shown in Figure9, the lever I99 engaging the abutment I91 so as to shift the horizontalbar l96 back to the position shown in Figure 9 in which the bevel gearIBI is effective and the bevel gear I99 is ineffective.

As the grinding of the knives proceeds it is necessary, as alreadymentioned, for the axis of the knife drum I' to be caused to approachthe grinding wheel. This is effected through the medium of theaforementioned ratchet wheel I26 which, in the operation of the grindingwheel I59, is caused by a pawl 2I9 to shift the journal bearings of theknife drum in the manner already described. The pawl 2I9 is pivoted at2H to a lever 2I2 mounted to swing about the axis of the shaft I28. Thelever 2I2 is connected by a link 2 l3 to a lever 2M pivoted about afixed point located just behind a shaft I15. As viewed in Figure 9 thelower end of the lever 2M is pivoted 10 at 2|5 to an extension 2I'6ofthe plunger 296.- Thus, as the lever I99 is caused to snap to-andfroduring the reciprocation of the grinding wheel I59, the lever 2I4 iscaused to siwng toand-fro, thus causing the pawl 2I9 to engage and shiftin succession the ratchet teeth on the ratchet wheel I26. This proceedsuntil the knives have been ground down to the required diameter and atthat point it is necessary for the movement to the knife drum I tocease. Therefore, the ratchet wheel I26 carries a cam member 2I1 which,at the point where the knives have been properly sharpened, engages thepawl 2I9 and lifts it aboutthe pivot 2 so as to prevent its furtherengagment with the ratchet wheel I26. Thereupon the operator can stopthe electric motor I66 for the grinding wheel I59, and also stop thetraversing movement of the carriage I54 by actuating the dog clutchcomprising the members I19 and HI. He then actuates the hand wheel I21to return the axis of the knife drum to the operative position in whichthe knives can sever the tobacco. It will be appreciated also that thepawl 2I9 can easily be moved by hand away from the ratchet wheel I26 toenable the manual movement of the knife drum axis to take place in theopposite direction, towards the grinding wheel, for the grindingprocess.

It may be mentioned that the dog member I19 to which the shaft I15 isclutched as required, is mounted on a shaft 229 having at its outer enda worm wheel 22I (Figure 2) in mesh with a worm 222 carried by a shaft223 bearing a bevel wheel 224. The bevel wheel 224 is in mesh with thebevel wheel 225 on a countershaft connected by gears 49 and 4| to theshaft 42 (Figure 1) carrying the pulley Wheel 43 driven by the motor 46.

- The machine is provided with a suction pump 226 driven by the belt 63which may be connected by a flexible pipe (not shown) to a trough 221beneath the grinding wheel I59 to remove the products of grinding.

I claim: Y

1. A machine for cutting leaf tobacco and the like comprising, incombination, a knife assembly mounted to rotate about a substantiallyhorizontal axis and including a plurality of knives equidistantlydistributed about said axis means for projecting the knives to increasethe cutting diameter of the knife assembly, means on one side of saidassembly for feeding tobacco thereto to be cut, mechanism on the otherside of said assembly for grinding said knives, means for moving saidknife assembly towards a position adjacent said feeding means forcutting tobacco and towards a second position adjacent said grindingmechanism for grinding said knives,.and means for rotating said knifeassembly in each said position.

2. A machine for cutting leaf tobacco and the like comprising, incombination, a knife assembly mounted to rotate about a substantiallyhorizontal axis and including a plurality of knives distributed aboutsaid axis means for projecting the knives to increase thecuttingdiameter of the knife assembly, means on one side of said assembly forfeeding tobacco thereto to be cut, mechanism onthe other side of saidassembly for grinding saidknives, bearing members supporting said knifeassembly and mounted for reciprocatory movement, a rotatable member,mechanism interposed between said rotatable member and said bearingmembers for movin said knife assembly towards a position adjacentauwgaee:

said rotatablemember is turned in the other:

direction, andmeans for'rotating said knife as-- zontal axis andincluding a plurality of" knives distributed about said axis; meansfolrotating said knife assembly'about' said axis, means onone side ofsaid assembly for feeding tobacco: thereto to be cut, a' grinding wheelon the otherside of said assembly, automatiemechanism for moving saidgrinding wheel to-and-fro parallel to said axis, positioningrnean-s formoving said knife assembly towardssaid tobaccofeeding means and awayfrom said grinding wheel and then away from said tobacco feeding meansand towards said grinding'wheel, and mechanism responsive to saidautomatic mechanismfor actuating said positioning means to feed saidknife assembly in small steps towards said grinding wheel during theoperation of the latter;

4. A machine for cutting leaf tobacco and'the like comprising,incombination, a knife assembly mounted to rotate about a-substntiallyhorizontal axis and including aplurality of knives distributed aboutsaid axis, means for rotating said knife assembly about said axis, meanson one side of said assembly for feeding tobacco thereto to be cut, agrinding wheel on the other side-of said assembly; automatic mechanismfor moving said grin-ding'wheel to-an'd -fio' parallel to said axis; afi'xed dressing tool' for dressing said grindingwheel and locating thelinea'long which said grinding wheel moves in said to-and fro movement.manually operable means for moving said grinding wheel into engagementwith said'tool. positioning means for moving said knife assembly towardssaid tobacco feeding means and away from said grinding wheeland thenaway from said tobacco feeding means and towards said grinding wheel,and mechanism respon ive to said automatic mechanism for actuating'saidpositioning means to feed-'saidknife assembly-in small ste s towardssaid grinding wheel during-the operation of the latter;

5. A machine for cutting leaftobacco and the like comprising incombination. a knife assembly mounted to-rotate'about a sub-tantiallyhorizontal axis and inc uding a plurality of knives substantiallyequidistantly distributed about said axis. said assembly furtherincluding mechanism inside the oath traversed by the rotating knives andoperative on all the' knives for' increasing simultaneouslythe radialdistance ofthe cutting edges 'of said knives from saidaxis. means on oneside of said assembly for feeding tobacco thereto to be cutLmechanism onthe other: side of said knife assembly for grinding said knives;meansfor movingaid assembly away, from said'grin'd ing mechanismand'towards'a position adjacent said feeding means for enablingsaid'assembly-tocut the tobacco and'then away from said feeding meansand towards a secondiposition adjacent said grinding mechanism to enablesaid assembly tobe harpened; and means for rotating said knife assemblyin each said position. v

6. A machine for cutting leaf tobacco and the like comprising. incombination, a knife drum mounted to rotate about a horizontal axis andprovided around its periphery with a substantial number of elements eachpresenting a clamping 12 surface; clampmembers alloca-ted:respectivelyto the surfaces, a cam associated with each clamp: member for thrustingupon and maintaining same iniclamping position, knives allocatedrespectively;

to the surfacesiandmaintained thereagainst by said clamp members; meansfor rotating said knife drum. about'said axis, means for feeding tobaccotowards said knives to besevered by same, and members defining amouthpiece through which the tobacco is presented to'said knives, thedistance between the cutting edges of adjacent knivesbeing substantiallyequal to the maximumheight of the mouthpiece in a directiontangentialto-the path of 'theknives during cutting, whereupon thetobacco is-at'all times being cut by one knifeiandone-knife only,andmeans for simultaneously shifting the cutting-edges ofsaid knivesfurther-from their respective clamping devices;

'7. A machine for cutting leaf tobacco and the like'comprising, incombination, a knife assembly mounted to rotate'about an axisandprovided around said axis with clamping devices, knives allocatedrespectively to said devices, each knife having its faces held by its,respective clamping: device,- said assembly further comprising leversoperatively associated with the edges of said knives remote from theircutting edges, means for rotating saidknife assembly: about said axisand means for actuating said levers for simultaneouslyshifting thecutting edges of a plurality of said knives further from theirrespective clamping devices.

8'. A machine for cutting leaf tobacco and the like, comprising,incombination, a drum, means distributed around the periphery of'saiddrum for holding knives substantially tangentially of the drum, knivesmounted in said holding means, asecond' drum mounted within saidfirst-mentioned drum, levers interposed between said knives and saidsecond drum, means for rotating said second drum with respect to saidfirst-mentioned drum to actuate said levers to increase the distance'between the cutting edge of each knife and its respectiveholdingmeans,means for rotating both said drums as a unit; and means forfeedingtobacco towards the-path traversed by said knives to be severed bysame;

9'; A machine for cutting leaf tobacco and the likeacomprising, incombination, rotatable knife mechanism for cutting tobacco, and meansfor feeding leaf tobacco and the like towards said knife'mechanism, saidmeans comprising upper and lowerjaws adjacent said knife mechanismand-upper andlower endless" feed bands for feed ing tobacco towards saidjaws, said upper jaw being mounted on parallel links constituting aparallelogram linkage arranged to svn'ng about fixed points located in asubstantially vertical plane including the axis of rotation of the knifeassembly, means for urging said upper jaw towards said lower jaw, aroller for one end of said upper: endless. feed band" mounted on saidjaw, and a driving roller, for theremote end of said upper endlessfeed'band', said driving-roller being mounted to'moveto-and-fro inresponse to the movements of said upper jaw.

10'. Machine forcutting leaf tobacco and the like-comprising, incombination, a knife drum mounted to rotate about ahorizontal axis andprovided around its periphery with a number of knife holding units eachpresenting a clamping surface, clamp members allocated respectively tothe surfaces, closely spaced knives allocated'respectively to thesurfaces and mounted thereagainst bysaidclamp members, saidknife holdingunits forming a continuous annular assembly REFERENCES CITED around saiddrum, each of said clamp members being formed at one side with a, l tadapted t The following references are of record in the receive andtemporarily retain the tobacco severed file Of this patent:

by its associated knife, the slot being substantially 5 UNITED STATESPATENTS wholly located, with respect to the direction of rotation,behind the cutting edge of the associated Number Name Date knife, meansfor rotating said knife drum about 848,066 f f 26, 1907 939,770 WilliamsNov. 9, 1909 said axis and means for feeding tobacco towards said drum,and air jets so positioned at a suitable 10 1,445,218 Koch 1923 pointbeside said rotating drum as to expel the 1,769,870 Traud July 1930tobacco from said slots as they pass by the jets. 242L879 Lorent? June1938 2,182,900 Mcllvried Dec. 12, 1939 PATRICK QUINTIN ROBERTSCI-IREIBER. FOREIGN PATENTS 15 Number Country Date 12.221 Australia192B

